I bet he has his old Broom Handle in there .
And I think thats where it is in photo (you can just see Bens hand he is siting on bike) In use if it settles lower we may need to up the springs ( if not perhaps a broom handle may be called for )Timetraveller's instructions say:
"Then the rider should sit on the bike, or get someone of a similar weight to do that and then check that the front of the lower link is now slightly above the rear of the link."
In your photograph, it looks (to me) like the front of the link is below the rear concentric end of the link. If Ben has his weight on the bike wouldn't that suggest the springs are too long or too heavy? (Or Ben is too light. )And I think thats where it is in photo (you can just see Bens hand he is siting on bike) In use if it settles lower we may need to up the springs ( if not perhaps a broom handle may be called for )
got these with a set of old spring boxes they are about 3 inches long Someone must have also used this mod in AustraliaJacking up the rear end has always been a trick to get much better cornering out of a Vincent. This was used in the 1960's by Coburn Benson on the Flash. He made spring box bolts that were 3" long and put them on both ends of the rear spring boxes. Later, Reg Bolton did the same thing with his mod:
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I suggested this mod to Carleton Palmer. He tried it and never took it off. He got three national championships with it on the bike. I should also mention that we bolted these mods up tight and did not use the small divot for the seat tube, just two triangular plates fully tightened, but otherwise followed Reg's drawing.
I think the 1-1/4" is a very good choice on a racer. I think that is about a 4 degree decrease in the rake, bringing it down to 26 or 27 degrees.
The Horners also used this concept on the Goodwood racer to get better handling. It is relatively easy to do with a coil-over on the rear. Much like the extended rear spring bolts it allows you to reduce the rake. Patrick Godet uses a longer F106/1, as I do also.
Generally, mods on the rear will not create a wobble problem. The primary cause of a wobble is due to a lightening of the front end (of some type). With the stock Girdraulic it is the fork seizing that causes the tire to bounce ever so slightly. This loss of front wheel traction is just enough to disturb the grip and allow a wobble to develop. This does not mean that a crazy set-up on the rear can't contribute or exacerbate a problem.
As for where the spindles reside, I think folks with the JE stem should follow Norman's advice. As for my own stem, which is slightly different, I tell users that the spindle position is not important in terms of the handling. (I think Norm is saying it is important in terms of adjusting the ride.) Both designs get rid of the fork seizing under braking, which doesn't cure the wobble problem, but it does a good job of minimizing it.
I certainly wish that more folks could try the handling of these race bikes. The results are unbelievable as Greg writes. Cam Donald also wrote about the unexpected fantastic handling of the Grey Flash, considering what he had heard about Vincent handling. Both Cam and Dave Roper won their first races on these bikes with close to no practice time. Beau Beaton (Horners' rider) rode Greg's racer and was really impressed with its ability.
David
Never seen those before, Learning all the time .got these with a set of old spring boxes they are about 3 inches long Someone must have also used this mod in Australia
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